Fairchild Semiconductor DM74LS157CW, DM74LS157SJ, DM74LS157N, DM74LS157MX, DM74LS157M Datasheet
© 2000 Fairchild Semiconductor Corporation DS006396 www.fairchildsemi.com
September 1986
Revised April 2000
DM74LS157 • DM74LS158 Quad 2-Line to 1-Line Data Selectors/Multiplexers
DM74LS157 • DM74LS158
Quad 2-Line to 1-Line Data Selectors/Multiplexers
General Description
These data selectors/multiplexers contain inverters and
drivers to supply full on-chip da ta selection to the fo ur output gates. A separate strobe input is provided. A 4-bit word
is selected from one o f two sources and is route d to the
four outputs. The DM 74LS 157 p resent s true dat a where as
the DM74LS158 presents inverted data to minimize propagation delay time.
Applications
• Expand any data input point
• Multiplex dual data buses
• Generate four functions of two variables
(one variable is common)
• Source programmable counters
Features
■ Buffered inputs and outputs
■ Typical Propagation Time
DM74LS157 9 ns
DM74LS158 7 ns
■ Typical Power Dissipation
DM74LS157 49 mW
DM74LS158 24 mW
Ordering Code:
Devices also availab le in Tape and Reel. Specify by appending th e s uffix let t er “X” to the ordering code.
Connection Diagrams
DM74LS157 DM74LS158
Order Number Package Number Package Description
DM74LS157M M16A 16-Lead Small Outline Integrated Circuit (SOIC), JEDEC MS-012, 0.150 Narrow
DM74LS157SJ M16D 16-Lead Small Outline Package (SOP), EIAJ TYPE II, 5.3mm Wide
DM74LS157N N16E 16-Lead Plastic Dual-In-Line Package (PDIP), JEDEC MS-001, 0.300 Wide
DM74LS158M M16A 16-Lead Small Outline Integrated Circuit (SOIC), JEDEC MS-012, 0.150 Narrow
DM74LS158N N16E 16-Lead Plastic Dual-In-Line Package (PDIP), JEDEC MS-001, 0.300 Wide
www.fairchildsemi.com 2
DM74LS157 • DM74LS158
Function Table
H = HIGH Level
L = LOW Level
X = Don’t Care
Logic Diagrams
DM74LS157 DM74LS158
Inputs Output Y
Strobe Select A B DM74LS157 DM74LS158
HXXXLH
LLLXLH
LLHXHL
LHXLLH
LHXHHL
3 www.fairchildsemi.com
DM74LS157 • DM74LS158
Absolute Maximum Ratings(Note 1)
Note 1: The “Absolute Maximum Ratings ” are those val ues beyond w hich
the safety of the device cannot be guaranteed. The device should not be
operated at these limits. The parametric values defined in the Electrical
Characteristics tables are not guaranteed at the absolute maximum ratings.
The “Recommend ed O peratin g Cond itions” t able w ill defin e the condition s
for actual device operation.
DM74LS157 Recommended Operating Conditions
DM74LS157 Electrical Characteristics
over recommended operating free air temperature range (unless otherwise noted)
Note 2: All typicals are at VCC = 5V, TA = 25°C.
Note 3: Not more than one output should be shorted at a time, and the duration should not exceed one second.
Note 4: I
CC
is measured with 4.5 V applied to all inputs and all outputs OPEN.
DM74LS157 Switching Characteristics
at VCC = 5V and TA = 25°C
Supply Voltage 7V
Input Voltage 7V
Operating Free Air Temperature Range 0°C to +70°C
Storage Temperature Range −65°C to +150°C
Symbol Parameter Min Nom Max Units
V
CC
Supply Voltage 4.75 5 5.25 V
V
IH
HIGH Level Input Voltage 2 V
V
IL
LOW Level Input Voltage 0.8 V
I
OH
HIGH Level Output Current −0.4 mA
I
OL
LOW Level Output Current 8 mA
T
A
Free Air Operating Temperature 0 70 °C
Symbol Parameter Conditions Min
Typ
Max Units
(Note 2)
V
I
Input Clamp Voltage VCC = Min, II = −18 mA −1.5 V
V
OH
HIGH Level Output Voltage VCC = Min, IOH = Max, VIL = Max, VIH = Min 2.7 3.4 V
V
OL
LOW Level VCC = Min, IOL = Max, VIL = Max, VIH = Min 0.35 0.5
V
Output Voltage IOL = 4 mA, VCC = Min 0.25 0.4
I
I
Input Current @ Max VCC = Max S or G 0.2
mA
Input Voltage VI = 7V A or B 0.1
I
IH
HIGH Level VCC = Max S or G 40
µA
Input Current VI = 2.7V A or B 20
I
IL
LOW Level VCC = Max S or G −0.8
mA
Input Current VI = 0.4V A or B −0.4
I
OS
Short Circuit Output Current VCC = Max (Note 3) −20 −100 mA
I
CC
Supply Current VCC = Max (Note 4) 9.7 16 mA
From (Input)
RL = 2 kΩ
Symbol Parameter
To (Output)
CL = 15 pF CL = 50 pF Units
MinMaxMinMax
t
PLH
Propagation Delay Time
Data to Y 14 18 ns
LOW-to-HIGH Level Output
t
PHL
Propagation Delay Time
Data to Y 14 23 ns
HIGH-to-LOW Level Output
t
PLH
Propagation Delay Time
Strobe to Y 20 24 ns
LOW-to-HIGH Level Output
t
PHL
Propagation Delay Time
Strobe to Y 21 30 ns
HIGH-to-LOW Level Output
t
PLH
Propagation Delay Time
Select to Y 23 28 ns
LOW-to-HIGH Level Output
t
PHL
Propagation Delay Time
Select to Y 27 32 ns
HIGH-to-LOW Level Output
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